Albert Dietrich: Beiträge zur Kakteenkunde. In: Allgemeine Gartenzeitung. Band 19, Nummer 44, 1. November 1851, S. 346–347 (online).
N. L. Britton, J. N. Rose: The Cactaceae. Descriptions and Illustrations of Plants of the Cactus Family. BandIV. The Carnegie Institution of Washington, Washington 1923, S.28 (online).